Processes for the preparation of organopolysiloxane resins are already known. For example, U.S. Pat. No. 4,707,531 (Toray Silicone Co., Ltd.; issued on Nov. 17, 1987) describes a process for the preparation of organopolysiloxane resins in which alkoxysilane is metered into a mixture of disiloxane and/or trialkylsilane and aqueous hydrochloric acid containing at least 5% by weight of hydrogen chloride. The use of large amounts of hydrogen chloride allows the molecular weight of the resin to be controlled here by choosing the ratio of the molar contents of monofunctional units to tetrafunctional units. U.S. Pat. No. 5,070,175 (Shin-Etsu Chemical Co., Ltd.; issued on Dec. 3, 1991) describes a process for the preparation of an organopolysiloxane having tetrafunctional siloxane units by heating a mixture of alkyl silicate and organosilane or oligomeric organosiloxane compound at a temperature which is at least 10.degree. C. above the boiling point of the mixture under normal pressure in the presence of water and a catalyst containing sulfonic acid groups in a closed reaction vessel. The German patent application, file number P 42 16 139.8 (Wacker-Chemie GmbH; applied for on May 15, 1992) describes a process for the preparation of an organopolysiloxane resin by acid hydrolysis of silanes or partial hydrolyzates thereof and after-treatment with a base in the presence of an organic solvent which is insoluble in water.